Many child-resistant closure systems require the user to deflect a tab extending from the container in order to remove the closure when it is installed on the container in a child resistant position. For example, U.S. Pat. No. 5,899,348 describes a closure having a bottom peripheral skirt/flange with a locking lug disposed underneath the skirt, while the container of the '348 Patent has a deflectable release element disposed at an interruption of a neck ring/rim/radial skirt/flange extending from the outer circumference of the container. The release element includes a locking lug axially aligned with the peripheral skirt of the closure when the closure is being installed onto the container such that the locking lug of the closure is operable to engage the locking lug of the container. Engagement of the corresponding locking lugs prevents the closure from being turned in the counter-clockwise direction, and thus prevents the closure from being removed from the container. In order to disengage the locking lugs and remove the closure, the user pushes down on a portion of the deflectable release element that extends out from the skirt/flange of the closure and the neck ring of the container.
Similarly, U.S. Pat. No. 6,508,373 describes a closure having a pair of diametrically opposed internal lugs beneath the closure thread that engage a stop log disposed on a deflectable tab of a container. It is noted that the tab of the container disclosed in the '373 Patent extends tangentially from the container's neck ring in order to provide a portion that extends from the container so that the user can access and deflect the tab when the closure is installed on the container. In order for the tab to deflect, the tab is separated from the external surface of the container and the opposing edge of the neck ring by a tangential slot as best shown in FIG. 7 of the '373 Patent.
One advantage touted by the '373 Patent is that its design can be fabricated by injection blow molding. However, while this may be true, the tangentially spaced tab separated from the container by the tangential slot renders the neck ring asymmetrical, which renders the container of the '373 Patent impossible to manufacture using a more efficient/desirable two-stage injection stretch blow molding method. In this regard, the plastic in a two-stage injection blow molding process is (1) molded into a preform and then ejected from the ejection mold during the injection cycle; and (2) fed after cooling via the container's neck through a reheat stretch blow molding machine during the blowing cycle. Once ejected from the original ejection mold, the “orientation” of the container during the fabrication process is lost. Thus, in order for the container to be properly handled and fed through the stretch blow molding machine during the second stage of the process, the neck of the container must be symmetrical to prevent any mishandling of the preforms by the machine. Similarly, other containers with a deflectable tab extending from the neck ring of the container, such as the container in the '348 Patent described above which is formed by injection molding, result in an assymetrical neck ring that prevents these types of containers from being used in two-stage injection injection stretch blow molding machines. The asymmetrical neck ring also prevents the containers from being used in automated dispensing machines due to the machines' trouble feeding containers with a tab element extending from one side.
Assignee of the present disclosure also describes a reversible closure system having yet another similar child resistant locking system as that of the '348 Patent and '373 Patent in U.S. Pat. Nos. 8,662,331 and 8,881,988, the entire contents of which are both incorporated herein by reference. With respect to the locking system described in the '331 Patent and '988 Patent and referring to FIGS. 1-5 of the present application, the reversible child-resistant closure system 10 includes an injection molded container 12 and a reversible child resistant closure 40.
As shown in FIG. 2, the container 12 generally includes a body 13 and a neck 14. The neck 14 includes a container engaging structure 18 disposed on an exterior of the neck 14, a container opening edge 20 defining a container opening 22, and a bottom edge 25 opposite the container opening edge 20 preferably defined by a neck ring or rim 24. The engaging structure 18 is operable to interact with a corresponding engaging structure 56 on the non-child resistant portion or engaging structure 58 on the child resistant portion of the reversible child resistant closure 40 to secure the closure 40 to the container 12. Disposed adjacent the rim 24 of the neck 14 is a deflectable locking structure 26 preferably disposed at an interruption of space in the rim 24. A locking lug 30 extends from a top surface 28 of the locking structure 26 towards the opening edge 20 of the container 12 for releasably engaging a corresponding locking lug 64 of the reversible child resistant closure 40 when the closure 40 is installed on the container 12 in a child-resistant configuration. For clarification purposes, the locking lug 30 of the container 12 is referred to herein as a locking tab, and the corresponding locking lug 64 of the closure 40 is referred to as a locking projection. In preferred embodiments, the locking tab 30 of container 12 includes a ramp or inclined surface 31 and a locking edge 33.
Referring to FIGS. 3A-3D, the corresponding closure 40 includes a first section 42 having a first edge 44 and a second section 46 having a second edge defined by flange 60. The first section 42 and second section 46 are separated by a solid divider 50 which prevents pharmaceuticals or other materials from exiting the opening 22 of the container 12 whether the one piece closure 40 is used in a child resistant configuration or a non-child resistant configuration. A circumferential sidewall 52 extends around the outer circumference of the closure 40 extending from the first edge 44 of the first section 42 to the flange 60 of the second section 46. The solid divider 50 and sidewall 52 forms a first section cavity 43 extending between the first edge 44 and the divider 50 and a second section cavity 47 extending from the bottom of flange 60 to the divider 50. Thus, the closure 40 provides a one-piece cap that can be lined on both sides as described more particularly in the '988 Patent.
The exterior surface 53 of the sidewall 52 preferably includes a gripping structure such as a plurality of knurls 55 for assisting a user to grip and rotate the closure 40 relative to the container 12. In certain embodiments, and as shown in FIGS. 3A-3D, the knurls 55 are separated into at least two sections with smooth sidewall sections 52 disposed between the sections with knurls 55. The smooth sections 52 are the result of sliding the molded closure 40 from the mold during the ejection process. At least two smooth sidewall sections 52 are typically required. FIGS. 3A-3D depict four smooth sidewall sections 52 for cosmetic purposes.
With continued reference to FIGS. 3A-3D, the first and second section 42, 46 of the closure 40 includes respective engaging structures 56, 58 preferably disposed on the interior surface 54 of sidewall 52 that are operable to interact for rotatable engagement with the complementary engaging structure or structures 18 on the container 12 to secure the closure 40 to the container 12. In this regard, when the closure 40 is applied to the container 12 in the child resistant configuration, engaging structure 58 of the closure 40 interacts with the engaging structure 18 of the container 12. On the other hand, when the closure 40 is inverted and applied to the container in the non-child resistant configuration, engaging structure 56 of the closure 40 interacts with the engaging structure 18 of the container 12. As shown in the Figures, the engaging structures 56 and 58 are preferably solid or segmented threads. However, other suitable engaging structures 56, 58 may be used as long as they are operable to interact with a corresponding engaging structure 18 of the container 12.
As shown best in the inverted view of FIG. 4, the flange 60 of the second section 46 is a peripheral skirt extending radially from the sidewall 52. The locking projection 64 extends radially inward from the inner surface 62 of the flange 60 and is operable to engage the locking tab 30 of the container 12 for preventing the closure 40 from rotating with respect to the container 12 when the closure is installed on the container 12 in the child resistant configuration. In this regard, the locking projection 64 of closure 40 preferably includes a ramp or inclined surface 66 and a locking edge 68. In operation, the closure 40, when applied to the container 12 in the child resistant configuration, is rotated in a closing direction, preferably clockwise, about the neck 14 of container 12 until the locking projection ramp 66 traverses the locking tab ramp 31. In order to remove the closure 40 from the container 12, a user must deflect the locking structure 26 so that the locking projection 64 disengages the locking tab 30. Referring to FIG. 1, a user preferably deflects the locking structure 26 downward to disengage the locking tab 30 of the container 12 from the locking projection 64 of the closure 40.
Thus, in order for the locking tab 30 to releasably engage the corresponding locking projection 64 of the closure 40, the locking structure 26 of this system 10, as well as many other child resistant systems known in the art, is yieldable or deflectable relative to the rim 24 of the container 12. Further, in order to deflect the locking tab 30, the locking structure 26 includes a push down tab 34 extending radially outward with respect to the flange 60 of the closure 40 and rim 24 of the container 12 (when the rim 24 is axially aligned with the flange 60) such that the locking structure is accessible to the user's fingers when the closure 40 is installed in the child resistant configuration. As noted above, the '348 and '373 Patents include similar deflectable tab structures extending from the container neck and the outer circumference of the closure flange in order to disengage their respective locking mechanisms.
While these types of closures systems are generally very effective in preventing a child from opening the closure, it is not impossible for children to open them (hence the name “child resistant”). In particular, a child playing with this type of closure system is likely to be drawn to the tab element extending from the container which, in some instances, may result in the child unintentionally pushing down on the tab element and removing the closure from the container. Also, the child may even figure out how to open the container, such as by watching their parents or even reading instructions displayed on the deflectable tab element, and then be able to do so on their own. What is needed therefore is a more discrete locking system that makes it more difficult for a child to recognize or understand how to open the closure system or otherwise prevents attracting child actions that result in the child unintentionally opening the container.
In another aspect, the ability to more efficiently manufacture a blow molded container incorporating a deflectable tab structure is needed.